1. Field of the Invention
The present invention relates to a thin film coil and an electronic device having the same, and more particularly, to a contactless power transfer apparatus capable of wirelessly transmitting power by using electromagnetic induction and a thin film coil used therefor.
2. Description of the Related Art
Recently, in order to charge a rechargeable battery installed in a mobile terminal or the like, a system for wirelessly transmitting power, namely, in a contactless manner, has been under research.
In general, a contactless power transfer apparatus includes a contactless power transmission apparatus transmitting power and a contactless power reception apparatus receiving and storing power.
Such a contactless power transfer apparatus transmits and receives power by using electromagnetic induction, and to this end, each contactless power transfer apparatus includes a coil therein.
A related art contactless power transfer apparatus is configured to have a coil wound parallel to a bottom surface thereof (i.e., an external contact surface). Also, a coil may be configured to be fixed to a bottom surface by an adhesive, a bonding sheet, or the like.
However, in the related art, a general wire-type coil is employed. Thus, coils are wound in an overlapping, stacked manner. This may cause a defect in which the thickness of a contactless power transfer apparatus is increased due to the thickness of the coil and the number of windings of coils.
Thus, in order to keep up with the recent trend in which relatively thinner devices are preferred, a development of a thinner contactless power transfer apparatus is required.
Also, the related art largely uses a single line type coil, so an AC resistance value may be increased due to an eddy current, a skin effect, or the like, at a low frequency, to thereby cause loss.